summaryrefslogtreecommitdiff
path: root/drivers/serial/serial_s3c44b0.c
diff options
context:
space:
mode:
authorWolfgang Denk <wd@denx.de>2009-04-02 00:24:33 +0200
committerWolfgang Denk <wd@denx.de>2009-04-02 00:24:33 +0200
commitdfc91c33957c95da34e3888dc87912d5c15a7603 (patch)
treed5fd6bd3818d817ea618bb9c19330633a71ab1bb /drivers/serial/serial_s3c44b0.c
parentc123098035be8bae3859bbfbd06861f197c07631 (diff)
parent0fc4f64c59873a47d555dd66bad25797d4ecb0ed (diff)
downloadu-boot-imx-dfc91c33957c95da34e3888dc87912d5c15a7603.zip
u-boot-imx-dfc91c33957c95da34e3888dc87912d5c15a7603.tar.gz
u-boot-imx-dfc91c33957c95da34e3888dc87912d5c15a7603.tar.bz2
Merge branch 'master' of git://git.denx.de/u-boot-arm
Diffstat (limited to 'drivers/serial/serial_s3c44b0.c')
-rw-r--r--drivers/serial/serial_s3c44b0.c218
1 files changed, 218 insertions, 0 deletions
diff --git a/drivers/serial/serial_s3c44b0.c b/drivers/serial/serial_s3c44b0.c
new file mode 100644
index 0000000..95d0266
--- /dev/null
+++ b/drivers/serial/serial_s3c44b0.c
@@ -0,0 +1,218 @@
+/*
+ * (C) Copyright 2004
+ * DAVE Srl
+ * http://www.dave-tech.it
+ * http://www.wawnet.biz
+ * mailto:info@wawnet.biz
+ *
+ * (C) Copyright 2002-2004
+ * Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <common.h>
+#include <asm/hardware.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* flush serial input queue. returns 0 on success or negative error
+ * number otherwise
+ */
+static int serial_flush_input(void)
+{
+ volatile u32 tmp;
+
+ /* keep on reading as long as the receiver is not empty */
+ while(UTRSTAT0&0x01) {
+ tmp = REGB(URXH0);
+ }
+
+ return 0;
+}
+
+
+/* flush output queue. returns 0 on success or negative error number
+ * otherwise
+ */
+static int serial_flush_output(void)
+{
+ /* wait until the transmitter is no longer busy */
+ while(!(UTRSTAT0 & 0x02)) {
+ }
+
+ return 0;
+}
+
+
+void serial_setbrg (void)
+{
+ u32 divisor = 0;
+
+ /* get correct divisor */
+ switch(gd->baudrate) {
+
+ case 1200:
+#if CONFIG_S3C44B0_CLOCK_SPEED==66
+ divisor = 3124;
+#elif CONFIG_S3C44B0_CLOCK_SPEED==75
+ divisor = 3905;
+#else
+# error CONFIG_S3C44B0_CLOCK_SPEED undefined
+#endif
+ break;
+
+ case 9600:
+#if CONFIG_S3C44B0_CLOCK_SPEED==66
+ divisor = 390;
+#elif CONFIG_S3C44B0_CLOCK_SPEED==75
+ divisor = 487;
+#else
+# error CONFIG_S3C44B0_CLOCK_SPEED undefined
+#endif
+ break;
+
+ case 19200:
+#if CONFIG_S3C44B0_CLOCK_SPEED==66
+ divisor = 194;
+#elif CONFIG_S3C44B0_CLOCK_SPEED==75
+ divisor = 243;
+#else
+# error CONFIG_S3C44B0_CLOCK_SPEED undefined
+#endif
+ break;
+
+ case 38400:
+#if CONFIG_S3C44B0_CLOCK_SPEED==66
+ divisor = 97;
+#elif CONFIG_S3C44B0_CLOCK_SPEED==75
+ divisor = 121;
+#else
+# error CONFIG_S3C44B0_CLOCK_SPEED undefined
+#endif /* break; */
+
+ case 57600:
+#if CONFIG_S3C44B0_CLOCK_SPEED==66
+ divisor = 64;
+#elif CONFIG_S3C44B0_CLOCK_SPEED==75
+ divisor = 80;
+#else
+# error CONFIG_S3C44B0_CLOCK_SPEED undefined
+#endif /* break; */
+
+ case 115200:
+#if CONFIG_S3C44B0_CLOCK_SPEED==66
+ divisor = 32;
+#elif CONFIG_S3C44B0_CLOCK_SPEED==75
+ divisor = 40;
+#else
+# error CONFIG_S3C44B0_CLOCK_SPEED undefined
+#endif /* break; */
+ }
+
+ serial_flush_output();
+ serial_flush_input();
+ UFCON0 = 0x0;
+ ULCON0 = 0x03;
+ UCON0 = 0x05;
+ UBRDIV0 = divisor;
+
+ UFCON1 = 0x0;
+ ULCON1 = 0x03;
+ UCON1 = 0x05;
+ UBRDIV1 = divisor;
+
+ for(divisor=0; divisor<100; divisor++) {
+ /* NOP */
+ }
+}
+
+
+/*
+ * Initialise the serial port with the given baudrate. The settings
+ * are always 8 data bits, no parity, 1 stop bit, no start bits.
+ *
+ */
+int serial_init (void)
+{
+ serial_setbrg ();
+
+ return (0);
+}
+
+
+/*
+ * Output a single byte to the serial port.
+ */
+void serial_putc (const char c)
+{
+ /* wait for room in the transmit FIFO */
+ while(!(UTRSTAT0 & 0x02));
+
+ UTXH0 = (unsigned char)c;
+
+ /*
+ to be polite with serial console add a line feed
+ to the carriage return character
+ */
+ if (c=='\n')
+ serial_putc('\r');
+}
+
+/*
+ * Read a single byte from the serial port. Returns 1 on success, 0
+ * otherwise. When the function is succesfull, the character read is
+ * written into its argument c.
+ */
+int serial_tstc (void)
+{
+ return (UTRSTAT0 & 0x01);
+}
+
+/*
+ * Read a single byte from the serial port. Returns 1 on success, 0
+ * otherwise. When the function is succesfull, the character read is
+ * written into its argument c.
+ */
+int serial_getc (void)
+{
+ int rv;
+
+ for(;;) {
+ rv = serial_tstc();
+
+ if(rv > 0)
+ return URXH0;
+ }
+}
+
+void
+serial_puts (const char *s)
+{
+ while (*s) {
+ serial_putc (*s++);
+ }
+}